Dental instrument



F B. DAVIS. DENTAL INSTRUMENT.

APFLICATION FILED MAY 23, I917- Patented Jan. 13, 1920.

UNITED sTATEs PATENT OFFICE.

FRANK BRoUeHToN :oAvIs, oEEEIE, PENNSYLVANIA.

DENTAL INsTEUMENT.

To all whom it may concern:

Be it known that I, FRANK B. DAvis, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, have invented new and useful Improvements in Dental Instruments, of which the following is a specification.

This invention relates to dental instruments and consists in certain improvements in the construction thereof as willbe hereinafter fully described and pointedout in the claims.

More particularly the invention relates to dental toolswhich are employed for the purpose of reducing the roots of teeth or remova ing the enamel therefrom, and commonly known as root trimmers. The object of my invention is to provid a tool of this character which can be conveniently and efiiciently operated by the dentist with a minimum of discomfort to the patient, and at the same time a tool which may be used for the teeth of both the upper and lowerjaw and for the inside. as well as the outside of such teeth. h

Th invention is illustrated in the accompanying drawings as follows Figure 1 shows a front elevation of the tool.

Fig. 2 is a section on the line 22 in Fig. 1.

Fig. 3 is a section on the line 33 in Fig. 2.

Fig. 4 is a section on the line .t-1 in Figs. 1 and 2. v

Fig. 5 is a section on the line 55 in Fig. 2 showing a variation in positionof parts from that shown in Fig. 2. v

1 marks the bearing member. It is in the form of a round spindle and has the point or projection 2 which in use is placed in a socket in the face of the tooth being operated upon. 8 is a block slidingly mounted on the bearing member, 4: a sleeve extending from the block along the bearing member, and 5 a spring arranged around the bearing member and exerting pressure on the sleeve 4,

the spring having a base or anchor in the.

form of a shoulder 6 on th bearing member 1. 7 is a handle on the end of the bearing member, preferably secured thereto by a screw on the end of the bearing member. The bearing member may be moved through the block 3, the spring, however, tending to hold the block 3 downwardly on the bearing member.

Specification of Letters Patent. Patented J an. 13, 1920';

Application filed May 23, 1917. Serial No. 170,510.

I A tool actuating member Shas the arms 9' extending each side of the block 3 and, a pin 10 extends through these arms and through the block thus forming a pivotal mounting for the tool actuating member 8. A fiat spring 11 is secured to the end of the block 3 by a screw 12. This spring operating on the ends of the arms 9 tends to hold the tool actuating'memb'er 8 in its upper position but permits it to' swing so that the tool 13 carried by the tool actuating member may be swung toward'and from the point 2. The tool 13, has a cutting edge 14 by means of which the enamel may b'e'broken and stripped from the teeth.

A handle holding member 15 is pivotally. mounted onthe sleeve'e'and the handle 16 has a bifurcated end 17 pivot-ally secured to the handle holding member 15 by a pin 18. The arms of the end 17 have the surfaces 19 which engage the arms 9 of the tool actuat ing member 8 so that when the handle 16 is swung on the pivot 18 this downward move ment of theend 17 acting on the arms 9 forcibly moves the tool 13 toward the point 2." The handle 16 has a projection 16 extending substantially at right angles to the bearing member 1 with the tool in position. The handle 7 also extends substantially at right angles to this bearing member.

In the operation of the tool the point 2 is placed in the socket in the tooth, the handle 7 is grasped by the operator, the operator at the same timeengaging the projection 16 The handle 16 is first'forced toward the bearing member 1 so as to swing the tool 14 into engagement with the side of the tooth and the tool is then pulled longitudinally of the bearing member by the operator pulling the handle 16 toward the handle 7. This movement is opposed by the spring 5 and as soon as pressure is relieved by the operator the parts return to normal. The spring 5 forces the block 3' to its lower position and the spring 11 swings the handle 16 to its outer position. In this way the operator can not only exert a cutting pressure on the tool but a longitudinal action to the tool at the same time if he so desires.

In order that the tool mayv be operated within or without the tooth I provide for swinging the handle 16 around the bearing member and also swinging the handle 7 'so that the tool 13 may be reversed as to the position of the handles. Thehandle holding member 15 is rotatively mounted on the sleev 4: and is locked in position by a locking member 20. The locking member 20 is mounted on the sleeve 1 and has a detent 21 at its lower end which engages a tooth 22 on the handle holding member 15. There are two of these detents 21 and teeth 22 so that when the locking member 20 is raised so as to free the tooth the member 15 may be swung around to the opposite side of the tool.

The locking member has a slot 23 extending downwardly from its top and the sleeve 4 has a slot 24 extending downwardly from its top. A projection 25 is arranged on the bearing member 1 and this projection extends through the slots 23 and 24, thus locle ing these parts against turning. A nut 26 is arranged on the screw-threaded upper end of the sleeve 4. Thisengaging the projection 25 looks the teeth 22 in the detent 21. When it is desired to shift the position of the handle 16, the nut 26 is backed away allowing the lifting of the locking member sufficiently to accomplish this purpose. The nut 26 may be so adjusted that there is sufiicient play for the locking member 20 and the handle holding member 15 between the block 3 and nut 26 to permit the disengagement of the handle holding member without a movement of the nut 26. Under these conditions the spring 11 swinging the opposite end of the block 8 upwardly holds the detent 21 in the tooth 22.

I prefer to provide the nut 26 with a slot 27 which may come into register with the slots 23 and 24 so that the projection 25 may be freely withdrawn so that a very slight movement of the nut 26 will permit of the withdrawal of the projection 25 where this is desired. It will be noted that the projection 25 acting in the slots as a key in connection with the detent 21 and tooth 22 locks the parts against turning and in position so that the arms of the bifurcated end 17 will properly engage the arms 9.

It will be noted that by adjusting the nut 26 the closing movement of the jaws may be varied because the position of the pivot 18 will be brought toward or away from the block 8 so that a given movement of the handle 16 will produce more or less action of the block and consequently more or less action of the tool.

What I claim as new is 1. A dental tool of the character described, comprising a holding or bearing member, and a pivoted tool actuating member mounted on the bearing member, said members having opposed handle portions or grasps extending at substantially right angles to their shank portions. I

2. A dental tool of the character described, comprising a bearing member; a block slidingly mounted on the bearing member; a tool actuating member pivotally connected with the block; and a handle for actuating said tool actuating member.

3. A dental tool of the character described, comprising a bearing member; a head block slidingly mounted on the bearing member; a spring interposed between the member and block; a tool actuating member pivoted on the block; a handle for actuating the tool actuating member; and a spring tending to swing the tool actuating member on the block. I

4. A dental tool of the character described, comprising abearing member; a block slidingly mounted thereon; a tool actuating member pivoted to the block; and a spring between the tool actuatingmember and the block adapted to return, the tool actuating member when operated.

5. A dental tool of the character described, comprising a bearing member; a block slidingly mounted on said bearing member; a spring interposed between the block and bearing member; a tool actuating member pivoted on the block; a handle for actuating the tool actuating member; a spring tending to return the handle when actuated; and a handle on the bearing member, each of said handles having a grasp extending substantially at right angles to the bearing member.

6. A dental tool of the character described. comprising a bearing member; a block slidingly mounted on the bearing member; a tool actuating member pivotally mounted on the block; a pivoted handle for actuating the tool actuating member; and

means for adjusting the tool actuating member and handle relatively to each other to reverse the action of the tool actuating member relatively to the handle.

7. A dental tool of the character described, comprising a bearing member; a block slidingly mounted on the bearing member; a tool actuating member pivotally mounted on the block; a pivoted handle for actuating the tool actuating member; and means for adjusting thetool actuating member and handle relatively to each other to reverse the action of the tool actuating member relatively to the handle, said means comprising a screw-threaded and slotted sleeve extending from the block; a locking sleeve mounted on the screw threaded and slotted sleeve, said locking sleeve being slotted and having devices engaging the tool actuating member for locking said tool actuating member in different rotative adjustments; a projection on the bearing member extending into said slots; and a nut on the screw threaded and slotted sleeve engaging said projections.

8. A dental tool of the character described, comprising a bearing member; a block slidingly mounted on the bearing member; a tool actuating member pivotally mounted on the block; a pivoted handle for actuating the tool actuating member; and means for adjusting the tool actuating member and handle relatively to each other to reverse the action of the tool actuating member relatively to the handle, said means comprising a screw-threaded slot and sleeve extending from the block; a locking sleeve mounted on the bearing sleeve, said locking sleeve being slotted and having devices engaging the tool actuating member for looking said tool actuating member in difierent rota-tive adjustments; a projection on the bearing member extending into said slots;

i and a nut on the bearing sleeve engaging said projections, said nut having a slot permitting the passage of the projection when all of said slots are in register.

9. In a dental tool of the character described the combination of a bearing member; a block slidingly mounted on the bearing member; a tool actuating member pivotally mounted on the block; a pivoted handle for actuating the tool actuating memher; and means for adjusting the tool actuating member and handle relatively to each other to vary the movement of the tool with a given movement of the handle.

In testimony whereof I have hereunto set my hand.

FRANK BROUGHTON DAVIS. 

